When collecting a blood culture specimen from a patient allergic to shellfish, which antiseptic is appropriate?

Chlorhexidine gluconate is the appropriate antiseptic to use when collecting a blood culture specimen from a patient who is allergic to shellfish because it does not contain iodine, which is a component of povidone-iodine. Patients with shellfish allergies can sometimes have a cross-reactivity to iodine, leading to allergic reactions. Chlorhexidine gluconate is effective as an antiseptic, providing a broad spectrum of antimicrobial action that helps minimize the risk of contamination during the blood culture procedure. Its use is particularly preferred in healthcare settings for skin antisepsis because of its residual activity, offering long-lasting protection against microbes in the area where the blood is drawn.

Using hydrogen peroxide or isopropyl alcohol is less preferred for blood cultures as these antiseptics do not provide the same level of antimicrobial effectiveness or residual protection as chlorhexidine gluconate.